Asubprime mortgage is
a high-risk, high-interest loan
a federal bailout for major banks
a form of insurance on investments
a form of political capital

High-risk, high-interest loan.

Explanation:

The classical definition of a subprime mortgage is concerned to borrowers with lower credit ratings and it normally carries a higher interest rate.

It is good emphasize  that these loans  carry higher interest rate justified by the the greater risks associated with buyers that have poor credits.

basic principles: federalism, separation of powers, checks and balances, judicial review, representative democracy, limited government, rule of law, individual rights and responsibilities, consent of the governed, majority rule, popular sovereignty, equal protection.

it granted civil rights to african americans.